[fpc-pascal] RFD: CardDAV support library for FreePascal, call for ideas

[Michael Van Canneyt]

On Wed, 25 Sep 2013, Lukasz Sokol wrote:

> Hello,
>
> since I have not found anything on CardDAV related/written in/for FreePascal/Lazarus,
> (haven't googled with Delphi keyword thou)
>
> I'd like to send out some smoke signals, asking which way would the
> support for this kind of interaction (dare not call it a protocol)
> would be best fitting into FreePascal/Lazarus world.
>
> CardDAV itself is an extension of WebDAV and itself has its own RFC (RFC6532).
>
> I myself am trying to write a client connecting via CardDAV to a
> compatible server (built into my CRM, eGroupware) to request search and read
> addressbook entries.
>
> (it was the developers of the CRM in question indicated to me that XMLRPC is dead and support
> for it will be removed when they get a chance - that's why I'm doing this.)
>
> So far I got as far as copy/pasting example XML from the RFC and
> got a valid response from server, using THTTPSend from Synapse.
> http://wiki.freepascal.org/XML_Tutorial (and particularly the second XML2Tree procedure from
> http://wiki.freepascal.org/XML_Tutorial#Populating_a_TreeView_with_XML, with some mod of mine
> to not pass a TTreeView but a TTreeNodes object into it instead) came in handy to understand
> the structure of it.
>
> There are certain advantages of CardDAV over XMLRPC, which this post is too short to contain ;)
>
> I intend to keep it very simple at first, as it's enough for my purpose, to the point that the XML
> elements+attributes would be coded just as string concatenating operations and validated using
> TXMLDocument from dom.pas.
> Seems like the more complicated elements of DOM level 3 will need DOM.pas modifications too.
>
> But I'd like to know, if there is interest in making it 'more sentient', e.g. as
> a TDataSource/TDataSet descendant directly talking to (reading, at first) DOM.pas's
> TXMLDocument/TDOMDocument, then to a THTMLSend or any such class of your liking?

I do not think that a TDataset descendent is needed. 
A simple collection based class will do just fine, and a class to handle transport.
I have one for WebDAV, and CardDav really is not so much different.

I also do not see why you would need alterations to DOM.pas, both WebDav and CardDav use plain and simple XML.

BTW. The RFC is 6352 instead of 6532.

Michael.